Forged Card Discrimination System

ABSTRACT

A forged card discrimination system, an authenticity determination information writing device and a forged card discrimination device which can directly utilize an existing cash card or a credit card of a magnetic recording type and is preferable to prevent abuse of a forgery card with low cost are provided. A forged card discrimination system  1  is configured to include a magnetic card read section  1   a,  magnetic card determination section  1   b,  and an authentic signal (analog signal) writing section 1 c,  reads all track data on the magnetic card as analog signal, and analyzes the waveform of the analog signal so as to determine authenticity of the magnetic card, in addition, when target magnetic card is an authentic card, performs writing analog signal data based on the original algorithm in a front part of writing position of STX signal and a rear part of writing position of ETX signal.

FIELD OF THE INVENTION

The present invention pertains to a forged card discrimination system,an authenticity determination information writing device, and a forgedcard discrimination device to discriminate forgery of magnetic cardssuch as a credit card and a cash card.

BACKGROUND

In recent years, the damage from skimming of a cash card increases. As atrick of a crime, there is a spy camera, a hacking that abuses anetwork, or the like, and unauthorized use of a forged cash card. Thefrequency of these crimes is increasing as well. Currently, effectivemeasures to prevent these cannot be found. The amount of damage with aforged credit card from 2003 to 2005 is estimated to be around40-billion-yen a year. The credit industry offers users protection if auser notices the damage, but many users suffer the damage withoutnoticing it. The credit company does not suffer directly the damage,because it has collected the use charges in which an amount of damageassumed beforehand is added as an official fee from a store and a user.

Recently, a chip card (IC card) or a biometrics authentication systemhas been adopted to prevent the damage with a forged card. However, thechip card and biometrics authentication system do not completelyeliminate the crimes, and need a great investment because theintroductory cost is expensive. In addition, like the above creditcompany, a user must bear an unnecessary usage fee to that the amount ofdamage is assumed is not assumed by the system. Further, in view of anaspect of customer security, such as raises of the usage fee, creditcompanies also suffer great loss.

Thus, the invention disclosed herein is adapted for attention to such aunsolved problem that a prior art has, and has a purpose to provide aforged card discrimination system, an authenticity determinationinformation writing device, and a forged card discrimination devicewhich can directly utilize an existing cash card or a credit card of amagnetic record type and is preferable to prevent abuse of a forgerycard with low cost.

SUMMARY

Disclosed herein are embodiments of a forged card discrimination system.One embodiment of a forged card discrimination system whichdiscriminates whether or not a magnetic card is a forged card, themagnetic card having a magnetic recording medium in which an approvalsignal data for approving a card is written in a predetermined recordposition comprises an encryption determination means which determineswhether or not the magnetic card is encrypted based on encryptiondetermination data; an authentic signal writing determination meanswhich determines whether or not an authentic signal data is written in aregion except record region of the approval signal data in the magneticrecording medium of the magnetic card, when the encryption determinationmeans determined that the magnetic card was encrypted; an authenticsignal writing means which encrypts the approval signal data when theencryption determination means determined that the magnetic card was notencrypted, and writes the authentic signal data based on the approvedsignal data encrypted in a region except record region of the approvalsignal data of the magnetic recording medium and a forgery discriminatemeans which discriminates whether or not the magnetic card is a forgedcard based on the determination result of the authentic signal writingdetermination means.

Also disclosed are embodiments of an authenticity determinationinformation writing device which writes an authentic signal data fordetermining authenticity of the magnetic card in the magnetic recordingmedium of the magnetic card having a magnetic recording medium in whichan approval signal data for approving a card is written in apredetermined record position. One embodiment of the authenticitydetermination information writing device comprises an encryptiondetermination means which determines whether or not the magnetic card isencrypted based on encryption determination data; and an authenticsignal writing means which encrypts the approval signal data when theencryption determination means determined that the magnetic card was notencrypted, and writes the authentic signal data based on the approvedsignal data encrypted in a region except record region of the approvalsignal data of the magnetic recording medium.

Also disclosed herein are embodiments of a forged card discriminationdevice which discriminates whether or not a magnetic card is a forgedcard, the magnetic card having a magnetic recording medium in which anapproval signal data for approving a card is written in a predeterminedrecord position. One embodiment of a forged card discrimination devicecomprises an encryption determination means which determines whether ornot the magnetic card is encrypted based on encryption determinationdata; an authentic signal writing determination means which determineswhether or not an authentic signal data is written in a region exceptrecord region of the approval signal data in the magnetic recordingmedium of the magnetic card, when the encryption determination meansdetermined that the magnetic card was encrypted; and a forgerydiscrimination means which discriminates whether or not the magneticcard is a forged card based on the determination result of the authenticsignal writing determination means.

Another embodiment of a forged card discrimination system whichdiscriminates whether or not a magnetic card is a forged card, themagnetic card having a magnetic recording medium in which an approvalsignal data for approving a card is written in a predetermined recordposition comprises an encryption determination means which determineswhether or not the magnetic card is encrypted based on encryptiondetermination data; an authentic signal writing determination meanswhich determines whether or not an authentic signal data for determiningauthenticity of the magnetic card is written in the magnetic recordingmedium of the magnetic card, when the encryption determination meansdetermined that the magnetic card was encrypted, an authentic signalwriting means which encrypts data written in the magnetic recordingmedium to generate the authentic signal data based on cipher generationdata when the encryption determination means determined that themagnetic card was not encrypted, and writes generated authentic signaldata in the magnetic recording medium; and a forgery discriminationmeans which discriminates whether or not the magnetic card is a forgedcard based on the determination result of the authentic signal writingdetermination means.

Yet another embodiment of a forged card discrimination system whichdiscriminates whether or not a magnetic card is a forged card, themagnetic card having a magnetic recording medium in which an approvalsignal data for approving a card is written in a predetermined recordposition comprises an encryption determination means which determineswhether or not the magnetic card is encrypted based on encryptiondetermination data; an encryption synchronizing signal writing meanswhich encrypts a synchronizing signal data written in the magneticrecording medium based on the cipher generation data and writesencrypted synchronizing signal data in the magnetic recording medium; anencryption synchronizing signal writing determination means whichdetermines whether or not encrypted synchronizing signal data is writtenin the magnetic recording medium based on the cipher generation datawhen the encryption determination means determined that the magneticcard was encrypted; and a forgery discrimination means whichdiscriminates whether or not the magnetic card is a forged card based ondetermination result from the encryption synchronizing signal writingdetermination means.

Yet another embodiment of a forged card discrimination system whichdiscriminates whether or not a magnetic card is a forged card, themagnetic card having a magnetic recording medium in which an approvalsignal data for approving a card is written in a predetermined recordposition comprises a public key data writing determination means whichdetermines whether or not a public key data is written in the magneticrecording medium of the magnetic card; a password data acquisition meanswhich acquires a password data; an authentic signal writingdetermination means which determines whether or not an authentic signaldata for determining authenticity of the magnetic card is written in themagnetic recording medium of the magnetic card, based on written publickey data and password data acquired by the password data acquisitionmeans, when the public key data writing determination means determinedthat the public key data was written in; a public key data writing meanswhich generates public key data and writes generated public key data inthe magnetic recording medium when the public key data writingdetermination means determined that the public key data was not written;an authentic signal writing means which encrypts data written in themagnetic recording medium to generate the authentic signal data based onpublic key data generated by the public key data writing means andpassword data acquired by the password data acquisition means, andwrites generated authentic signal data in the magnetic recording medium;and a forgery discrimination means which discriminates whether or notthe magnetic card is a forged card based on the determination result ofthe authentic signal writing determination means.

BRIEF DESCRIPTION OF THE DRAWINGS

The description herein makes reference to the accompanying drawingswherein like reference numerals refer to like parts throughout theseveral views, and wherein:

FIG. 1 is a block diagram illustrating an embodiment of forged carddiscrimination system according to the present invention;

FIG. 2 is a diagram which shows an example of a writing position ofauthentic signal data;

FIG. 3 is a flow chart which shows an operation process of forged carddiscrimination system;

FIG. 4A is a diagram which shows the signal waveforms before and afterencryption of data recorded to a magnetic stripe;

FIG. 4B is a diagram which shows the signal waveforms before and afterencryption of synchronizing signal data; and

FIG. 5 is a flow chart which shows operation process of forged carddiscrimination system in variation.

DETAILED DESCRIPTION

Hereinafter, embodiments of the invention disclosed herein will bedescribed with reference to the drawings.

FIGS. 1-3 are drawings which show a forged card discrimination system,an authenticity determination information writing device and a forgedcard discrimination device according to embodiments of the invention.

FIG. 1 is a block diagram of the forged card discrimination system 1.This forged card discrimination system 1 reads all track data on amagnetic card as an analog signal, and is a system which determines theauthenticity of a magnetic card by analyzing a waveform of the analogsignal. When a target magnetic card is not encrypted, an analog signalbased on original algorithm is written, in a front part of writingposition of an STX signal and a rear part of writing position of an ETXsignal. Herein, an STX signal is a start signal indicating data start ina card recognition region, and an ETX signal is an end signal indicatingthe data end in a card recognition region.

Forged card discrimination system 1 is constructed to include a magneticcard reading section 1 a, a magnetic card determination section 1 b andan authentic signal (an analog signal) writing, section 1 c as shown inFIG. 1. When the magnetic card is a cash card, operation of the forgedcard discrimination system 1 is explained. In the following discussion,it is assumed that an authentication process (identical personconfirmation) with the use of a password has been executed.

At first, in magnetic card reading section 1 a, JISII data recorded to amagnetic stripe of a cash card are read. Data read in magnetic cardreading section 1 a is sent to magnetic card determination section 1 b.

Next, magnetic card determination section 1 b determines whether or nota target cash card is encrypted. In this embodiment encryption status isdetermined whether or not specified data (data for encryptiondetermination) is included in the read JISII data. In other words it isdetermined to be encrypted when specified data is included, and it isdetermined not to be encrypted when specified data is not included.

When magnetic card determination section 1 b determines that the cashcard is not encrypted, authentic signal writing section 1 c generatesauthentic signal data by encryption a positioning data decided based onJIS II data, and writes the generated authentic signal (an analogsignal) data in front part of a writing position of STX signal data ofthe JISII data and in rear part of a writing position of ETX signaldata, in a region except writing region of JISII data of the cash card.

When magnetic card determination section 1 b determined that the cashcard was encrypted, authentic signal writing section 1 c determineswhether or not authentic signal (an analog signal) data is written infront part of a writing position of STX signal data and in rear part ofa writing position of ETX signal data, and discriminates, when theauthentic signal (an analog signal) data is written, that the cash cardis a authorized one (authentic card). On the other hand itdiscriminates, when an authentic signal data is not written in, that thecash card is a forged card. In other words, when a target magnetic cardis encrypted, writing presence of authentic signal data is determined.

When authentic signal data is written in, the target magnetic card isdiscriminated as a legitimate one (an authentic card). On the otherhand, when authentic signal data is not written in, a target magneticcard is discriminated as a forgery card. Herein, a record form of atrack in a magnetic card is a form that data is recorded on a track inF2F (Two-frequency) record form.

Referring to FIG. 2, a writing method of authentic signal (an analogsignal) data is explained with a diagram which shows an example of awriting position of authentic signal data. In writing process ofauthentic signal data, authentic signal writing section 1 c recognizes aSTX signal which exists at the beginning of a card reader recognitionregion, and, as shown in FIG. 2, writes authentic signal (an analogsignal) data at 0.5 [mm] front of writing position of a STX signal.Further, authentic signal writing section 1 c recognizes an ETX signalin the tail of a card reader recognition region and, as shown in FIG. 2,and writes authentic signal (an analog signal) data at 0.5 [mm] after ofwriting position of an ETX signal.

FIG. 3 is a flow chart which shows operation process of forged carddiscrimination system 1. A cash card is inserted into card insertionsection (not shown). In Step S100, magnetic card reading section 1 areads JISII data of one track from a magnetic stripe of a cash card. Instep S102, magnetic card determination region 1 b determines whether ornot a target cash card is encrypted. In other words, JISII data of onetrack is analyzed, and when specified data (data for encryptiondetermination) is included (Yes), step S104 is shifted to, and writingpresence of authentic signal data is determined.

When step S104 was shifted to, authentic signal writing section 1 cdetermines whether or not authentic signal (an analog signal) data iswritten in the a region except data recording region of JISII data in amagnetic stripe of a cash card, and when it is determined to be writtenin (Yes), step S106 is shifted to, and when it is determined not to bewritten in (No), step S108 is shifted to.

In step S106, magnetic card determination section 1 b determines that atarget cash card is an authentic card, and the process is finished. Onthe other hand, in step S108, magnetic card determination section 1 bdetermines that a target cash card is a forged card, and the process isfinished.

In step S102, if it is determined that a target cash card was notencrypted, the process proceeds to step S110, where data position of aencryption target is determined based on JISII data and the determinedposition data is encrypted to generate authentic signal data. Then, thegenerated authentic signal data is written in the region except datarecording region of JISII data in a magnetic stripe of a cash card, andthe process is finished.

In the above embodiment, determination process of encryption status inmagnetic card determination section 1 b corresponds to encryptiondetermination means, determination process of writing presence ofauthentic signal data in authentic signal writing section 1 ccorresponds to authentic signal writing determination means, generationand writing process of authentic signal data in authentic signal writingsection 1 c corresponds to authentic signal writing means, anddetermination process whether or not a target magnetic card is a forgerycard in magnetic card determination section 1 b corresponds to forgerydiscrimination means.

With such a configuration, it is possible to determine whether or notthe magnetic card is encrypted based on encryption determination data,by an encryption determination means, to determine whether or not anauthentic signal data is written in a region except record region of theapproval signal data in the magnetic recording medium of the magneticcard, when the encryption determination means determines that themagnetic card is encrypted, by an authentic signal writing determinationmeans, and to encrypt the approval signal data when the encryptiondetermination means determined that the magnetic card was not encrypted,and to write the authentic signal data based on the approved signal dataencrypted in a region except record region of the approval signal dataof the magnetic recording medium, by an authentic signal writing means.

In addition, it is possible to determine whether or not the magneticcard is a forged card based on the determination result of the authenticsignal writing determination means, by a forgery discrimination means.That is, it is possible to write authentic signal data for discriminatewhether or not these card are forged cards in a region except recordregion of signal data for approving card recorded in the magneticrecording medium (magnetic stripe) of the magnetic card such as magneticrecord type and credit card which are generally used (existing). Inaddition, it is possible to discriminate whether or not the magneticcard is a forged card, by determining the writing presence of theauthentic signal data for the magnetic card having an approval signaldata in which the authentic signal data is written.

With such a configuration, for example, it is possible to writeauthentic signal data in front and rear parts of STX signal and ETXsignal (in a region except record region of JIS II data of magneticstripe) indicating start and end of approval signal data (JIS II data)in cash card. A card forger steals approval signal data by making adevice for skimming recognize the above STX signal and ETX signal, butwith the above configuration, it is possible to prevent authentic signaldata from being stolen, because authentic data is written in a regionexcept record region of JIS II data.

FIG. 4A is a diagram showing the signal waveforms before and after ofencryption that are recorded to a magnetic stripe, and FIG. 4B is adiagram showing signal waveforms of before and after of encryption ofsynchronizing signal data. FIG. 5 is a flow chart which shows operationprocess of forged card discrimination system 1 in case of encryptionusing public key data, password data, and approval signal data.

In this variation, magnetic card determination section 1 b in the aboveembodiment determines writing presence of public key data (for example,it is comprised from a numeric strings of predetermined digits) for amagnetic card inserted into a card insertion section not shown(corresponding to determination process of encryption status in theabove embodiment). Further when public key data is not written in apredetermined record position of magnetic recording medium (a magneticstripe) in a magnetic card, it is determined that the magnetic card isnot encrypted, and authentic signal writing section 1 c generates publickey data and writes this in a predetermined record position of themagnetic stripe.

Since public key data is used in generation of authentic signal data andiscrimination of writing position and the like in processes ofsubsequent stages, when public key data is not written in apredetermined record position, it is predetermined that authentic signaldata also is not written in (that is, it is not encrypted). Thereforeauthentic signal writing section 1 c generates authentic signal (ananalog signal) data by encryption an analog signal data recorded in apredetermined record position of the magnetic stripe, based on publickey data subsequently generated, password data inputted by a card ownervia an input section not shown, and approval signal data written in themagnetic stripe.

Particularly, at first, data signal position to be encrypted isdetermined by public key data, password data and approval signal dataposition (these 3 data correspond to data for cipher generating data).Then as shown in chart of FIG. 4A, signal waveforms of the determinedposition in data signal waveforms (analog signal waveforms) recorded toa magnetic stripe are encrypted by transforming. The digital data towhich the analog signal waveforms before transformation are A/Dconverted and the digital data to which the analog signal waveformsbefore transformations are A/D converted become to be the same datacontents. Authentic signal writing section 1 c writes authentic signaldata generated by this encryption in a record position same as that of asignal before the encryption of a magnetic stripe. Here, writingposition of authentic signal data may be at least one of a front part ofwriting position of STX signal data and a rear part of writing positionof ETX signal data, or the other record position, same as description ofthe above embodiment.

On the other hand, in this variation, when it is determined that publickey data is written (that is, encrypted) in the predetermined recordposition in authentic signal writing section 1 c, it is determinewhether or not authentic signal data is written in a record positionspecified by these data based on the public key data, the password data,and the approval signal data. Also when it was determined that authenticsignal data was not written in, it is discriminated that a targetmagnetic card is a forged card in magnetic card determination section 1b.

Further, in this variation, synchronizing signal data written in amagnetic stripe of a magnetic card is encrypted based on above thepublic key data, the password data, and the approval signal data inauthentic signal writing section 1 c, and synchronizing signal databefore encryption is rewritten to the encrypted synchronizing signaldata. Here, synchronizing signal data is, for example, signal waveforms(an analog signal) data of a synchronizing signal when JISII datarecorded to a magnetic stripe of a cash card is read out.

Synchronizing signal data has a pulse waveform as shown in the chart ofFIG. 4B, and is written in a magnetic stripe. In this embodiment, awidth of pulse waveform is changed in a direction to broaden so thatsynchronizing signal data is encrypted (of course, a width may bechanged in a direction to narrow). This change of width is performed atthe level that does not lose all original function as a synchronizingsignal.

Then in authentic signal writing section 1 c when it is determined thatauthentic signal data is written in a determination of writing presenceof above authentic signal data, it is further determined whether or notabove encrypted synchronizing signal data is written in a recordposition specified by these data based on above public key data, abovepassword data, and above approval signal data. In this determinationwhen it is determined that encrypted synchronizing signal data was notwritten in, it is determined that a target magnetic card is a forgedcard in magnetic card determination section 1 b, and when it isdetermined that encrypted synchronizing signal data was written in, itis determined that a target magnetic card is an authentic card inmagnetic card determination section 1 b.

Referring to FIG. 5, a flow of operation process of forged carddiscrimination system 1, in a case of encryption using public key data,password data, and approval signal data, is explained. In addition, likeabove embodiment, a flow of operation process, when a magnetic card is acash card, is explained.

A cash card is inserted into card insertion section (not shown). Asshown in FIG. 5, step S200 is shifted to and JISII data of one trackfrom a magnetic stripe of a cash card is read out in magnetic cardreading section 1 a.

In step S202, in magnetic card determination section 1 b, it isdetermined whether or not public key data is written in a predeterminedrecord position in a magnetic stripe of a cash card. If it is determinedthat it was written in (Yes), the process proceeds to step S204, and ifit is determined that it was not written in (No), the process proceedsto step S214.

In step S204, in magnetic card determination section 1 b, it isdetermined whether or not password data of the inserted cash card ownerwas acquired. If it is determined that it was acquired (Yes), theprocess proceeds to step S206, and if it is not so (No), determinationprocess is repeated until it is acquired.

In step S206, in authentic signal writing section 1 c, it is determinedwhether or not authentic signal (an analog signal) data is written inthe record position specified based on public key data, password data,and JISII data in a magnetic stripe of a cash card, and when it wasdetermined that it was written in (Yes), step S208 is shifted to, andwhen it was not determined that it was not written in (No), step S212 isshifted to.

In step S208, in authentic signal writing section 1 c, it is determinedwhether or not encrypted synchronizing signal (an analog signal) data iswritten in the record position specified based on public key data,password data, and JISII data in a magnetic stripe of a cash card. If itis determined that it was written in (Yes), the process proceeds to stepS210, and if it is determined that it was not written in (No), theprocess proceeds to step S212.

In step S210, in magnetic card determination section 1 b, it isdetermined that the target card is an authentic card, and the process isfinished. On the other hand, in step S212, in magnetic carddetermination section 1 b, it is determined that the target card is aforged card, and the process is finished.

In addition, in step S202, when it is determined that public key datawas not written in a predetermined record position, the process proceedsto step S210 where, in magnetic card determination section 1 b, it isdetermined whether or not password data of the inserted cash card ownerwas acquired. If it is determined that it was acquired (Yes), theprocess proceeds to step S216, and if it is not so (No), determinationprocess is repeated till it is obtained.

In step S216, in authentic signal writing section 1 c, public key datais generated, the generated public key data is written in thepredetermined record position. Next, in step S218, in authentic signalwriting section 1 c, data signal waveform at the record positionspecified based on public key data, password data, and JISII data isencrypted to generate an authentic signal data, and the generatedauthentic signal data is written in the same record position as that ofa signal before encryption.

Next, in step S220, in authentic signal writing section 1 c,synchronizing signal data at the record position specified based onpublic key data, password data, and JISII data is encrypted to changesynchronizing signal data before encryption to encrypted synchronizingsignal data, and the process is finished.

In the above variation, determination process of writing presence(encryption status) of public key data in magnetic card determinationsection 1 b corresponds to encryption determination means, or public keydata writing determination means, determination process of writingpresence of authentic signal data in authentic signal writing section 1c corresponds to authentic signal writing determination means,generation and writing process of authentic signal data in authenticsignal writing section 1 c corresponds to authentic signal writingdetermination means, encryption and writing process of synchronizingsignal data in authentic signal writing section 1 c corresponds toencryption synchronizing signal writing section, determination processof writing presence of encrypted synchronizing signal data in authenticsignal writing section 1 c corresponds to encryption synchronizingsignal writing determination section, and process of discriminationwhether or not a target magnetic card in magnetic card determinationsection 1 b corresponds to forgery determination means. In the abovevariation, an input section (not shown) of password data corresponds topassword data acquisition means.

The above variation is configured to encrypt data at the record positionspecified based on public key data, password data, and approval signaldata (for example, JISII data) so as to generate authentic signal data.However, the invention is not limited to this, and can be configured toencrypt data at the record position specified based on at least one ofpublic key data, password data, and approval signal data (for example,JISII data) so as to generate authentic signal data. Further, it call beconfigured to use at least one of public key data, password data, andapproval signal data (for example, JISII data), not limited tospecification of the record position of encryption target, to the otherprocess relating encryption such as decision of an amount of variationof an analog waveform.

In the embodiment and the variation, a cash card that approval signaldata is JISII data was explained as an example, but, the presentinvention is not limited to this, can be applied to a magnetic card ofthe other data type such as a credit card that approval signal data isJISI data. In the embodiment and the variation, it is determined whetheror not the magnetic card is encrypted by determining whether or not thespecified data (data for determining encryption) or the public key datais written in the predetermined record position of the magnetic card.However the invention is not limited to this, for example, can beapplied to the other configuration to determine whether or not thetarget magnetic card is encrypted by accessing the external server suchas an information center and determining whether or not the public keydata is registered therein.

As discussed above, with a forged card discrimination system, anauthenticity determination information writing device and a forged carddiscrimination device according to the present invention, it is possibleto write authentic signal data capable of being determined easilywhether or not the magnetic card is a forged card in a existing magneticcard such as a cash card and a credit card, and to discriminate simplywhether or not the target magnetic card is a forged card based on theauthenticity signal data. Further, since authentic signals data iswritten in a different region from that of an approval signal data, itis possible to prevent the authentic signal data from being read out andanalyzed together with the approval signal data.

Since the authentic signal data is generated by encrypting data in apredetermined record position of the magnetic recording medium based onpublic key data, password data and approval signal data of the owner ofthe magnetic card, in accompanied with writing public key data in themagnetic card, it is possible to perform higher security encryption.

Further, in addition to encryption and writing of synchronizing signaldata written in the magnetic card and to determination of writingpresence of authentic signal data, forge discrimination is performed bydetermination of writing presence of the encrypted synchronizing signaldata. Therefore is possible to determine more surely whether a targetmagnetic card is a forged card.

With the configurations described herein, it is possible to determinewhether or not the magnetic card is encrypted based on encryptiondetermination data, by an encryption determination means to determinewhether or not an authentic signal data is written in a region exceptrecord region of the approval signal data in the magnetic recordingmedium of the magnetic card. when the encryption determination meansdetermines that the magnetic card is encrypted, by an authentic signalwriting determination means, and to discriminate whether or not themagnetic card is a forged card based on the determination result of theauthentic signal writing determination means, by a forgerydiscrimination means.

That is it is possible to determine whether or not a target magneticcard is a forged card based on authenticity of the approval signal data,and writing presence of authentic signal data written in a region exceptthe record region of the approval signal data, by the forged carddiscrimination system, or the authenticity determination informationwriting device.

It is possible to determine whether or not an authentic signal data iswritten in at least one of a front part of the record position of astart signal data indication a start position of the approval signaldata or a rear part of the record position of the end signal dataindicating a end position of the approval signal data, in a regionexcept the record region of the approval signal data of the magneticrecording medium by the authentic signal writing determination means.

It is possible to determine whether or not the magnetic card isencrypted based on encryption determination data by an encryptiondetermination means, to determine whether or not an authentic signaldata for determining authenticity of the magnetic card is written in themagnetic recording medium of the magnetic card, when the encryptiondetermination means determines that the magnetic card is encrypted by anauthentic signal writing determination means, to encrypt data written inthe magnetic recording medium to generate the authentic signal databased on cipher generation data when the encryption determination meansdetermined that the magnetic card was not encrypted, and to writegenerated authentic signal data in the magnetic recording medium by anauthentic signal writing means. It is possible to discriminate whetheror not the magnetic card is a forged card based on the determinationresult of the authentic signal writing determination means by a forgerydiscrimination means.

In addition, it is possible to write authentic signal data fordetermining authenticity of the magnetic card in the magnetic recordingmedium (magnetic stripe) when it was determined that it was notencrypted and to determine whether or not authentic signal data iswritten in the magnetic recording medium when it was determined that itwas encrypted. Thus it is possible to discriminate whether the magneticcard is a forged card by determining encryption status and writingpresence of the authentic signal data.

With such a configuration, it is possible to encrypt a synchronizingsignal data written in the magnetic recording medium based on the ciphergeneration data and to write encrypted synchronizing signal data in themagnetic recording medium by an encryption synchronizing signal writingmeans, to determine whether or not the encrypted synchronizing signaldata is written in the magnetic recording medium based on the ciphergeneration data, when the authentic signal writing determination meansdetermined that the authentic signal data was written by an encryptionsynchronizing signal writing determination means.

In additions it is possible to discriminate whether or not the magneticcard is a forged card based on determination result from the authenticsignal writing determination means and determination result from theencryption synchronizing signal writing determination means by theforgery discrimination means. Thus it is possible to encryptsynchronizing signal for reading out various data written in themagnetic recording medium (magnetic stripe) to write (rewrite) it in themagnetic recording medium, and to determine writing presence ofauthentic signal data and to determine writing presence of synchronizingsignal data after encryption, to the magnetic card, such as a cash cardand credit card, in which authentic signal data is written. Therefore itis possible to discriminate more surely whether or not the magnetic cardis a forged card.

Because synchronizing signal is a timing signal for reading outinformation written in the magnetic card, it cannot reach an idea toconvert it to synchronizing signal digital data for authenticitydetermination of the magnetic card. Therefore it brings about moreeffects in a point of making card forger not recognize encrypted part toencrypt this analog waveforms of synchronizing signal, for example, inthe state of holding a function as synchronizing signal so as to useauthenticity determination of the magnetic card. Thus it is possible tofurther improve the security. With such a configuration, it is possibleto determine whether or not the magnetic card is encrypted based onencryption determination data by an encryption determination means, toencrypt a synchronizing signal data written in the magnetic recordingmedium based on the cipher generation data and to write encryptedsynchronizing signal data in the magnetic recording medium by anencryption synchronizing signal writing means.

It is possible to determine easily whether or not the magnetic card isencrypted by presence of public key data set for every magnetic card inthe manner of being held in, for example, information center such as abank or being written in a magnetic recording medium (magnetic stripe)of a magnetic card. In addition, for example, by performing periodically(or for every time of utilization of service to which the presentinvention is applied) change of public key data and change of authenticsignal data for cash card and the like, it is possible to furtherimprove the security for utilization of service using this cash card. Itis possible to generate easily authentic signal data since encryption isperformed using at least one of the approval signal data, the public keydata, and the password data, and it is possible to perform furtherimproved encryption by performing encryption using all these data.

With such a configuration, it is possible to determine whether or not apublic key data is written in the magnetic recording medium of themagnetic card by a public key data writing determination means, toacquire a password data by a password data acquisition means, and todetermine whether or not an authentic signal data for determiningauthenticity of the magnetic card is written in the magnetic recordingmedium of the magnetic card, based on written public key data andpassword data acquired by the password data acquisition means, when thepublic key data writing determination means determined that the publickey data was written by an authentic signal writing determination means.In addition, it is possible to generate public key data and writesgenerated public key data in the magnetic recording medium when thepublic key data writing determination means determined that the publickey data was not written by a public key data writing means, and toencrypt data written in the magnetic recording medium to generate theauthentic signal data based on public key data generated by the publickey data writing means and password data acquired by the password dataacquisition means and writes generated authentic signal data in themagnetic recording medium by an authentic signal writing means. Inaddition, it is possible to discriminate whether or not the magneticcard is a forged card based on the determination result of the authenticsignal writing determination means by a forgery discrimination means.

That is, it is possible to write public key data for determiningauthenticity of authentic signal data in the magnetic recording medium(magnetic stripe) of the magnetic card such as magnetic record type andcredit card which are generally used (existing) and to write authenticsignal data for discriminate whether or not these card are forged cardsin the magnetic recording medium based on public key data and passworddata. Thus it is possible to discriminate whether or not the magneticcard is a forged card by determining writing presence of authenticsignal data based on public key data and password data for the magneticcard such as cash card and credit card in which public key data andpassword data are written.

It is possible to use that credit card or cash card in ATM and the likeof the other system which does not apply the present system, even afterwriting encrypted synchronizing signal in, by changing a width of analogwaveform of synchronizing signal within cope in which a function assynchronizing signal can be conducted in the same way as beforechanging. It is possible to perform encryption using approval signaldata in addition to public key data and password data. Therefore it ispossible to perform higher security encryption for synchronizing signaldata.

While the invention has been described in connection with what ispresently considered to be the most practical and preferred embodiment,it is to be understood that the invention is not to be limited to thedisclosed embodiments but, on the contrary, is intended to cover variousmodifications and equivalent arrangements included within the spirit andscope of the appended claims, which scope is to be accorded the broadestinterpretation so as to encompass all such modifications and equivalentstructures as is permitted under the law.

1. A forged card discrimination system which discriminates whether ornot a magnetic card is a forged card, the magnetic card having amagnetic recording medium in which an approval signal data for approvinga card is written in a predetermined record position, the forged carddiscrimination system comprising: an encryption determination meansconfigured to determine whether or not the magnetic card is encryptedbased on encryption determination data; an authentic signal writingdetermination means configured to determine whether or not all authenticsignal data is written in a region outside of record region of theapproval signal data in the magnetic recording medium of the magneticcard, when the encryption determination means determines that themagnetic card is encrypted; an authentic signal writing means configuredto encrypt the approval signal data when the encryption determinationmeans determines that the magnetic card was not encrypted, andconfigured to write the authentic signal data based on the approvedsignal data encrypted in a region outside of the record region of theapproval signal data of the magnetic recording medium; and a forgerydiscrimination means configured to discriminate whether or not themagnetic card is a forged card.
 2. The forged card discrimination systemaccording to claim 1, wherein the authentic signal writing means isconfigured to write the authentic signal data in at least one of a frontpart of the record position of a start signal data indicating a startposition of the approval signal data and a rear part of the recordposition of an end signal data indicating an end position of theapproval signal data, in the region outside of the record region of theapproval signal data of the magnetic recording medium; and wherein theforgery discrimination means is configured to discriminate whether ornot the magnetic card is a forged card based on the authentic signalwriting determination means determination.
 3. An authenticitydetermination information writing device configured to write anauthentic signal data for determining authenticity of a magnetic card ina magnetic recording medium of the magnetic in which an approval signaldata for approving a card is written in a predetermined record position,the authenticity determination information writing device comprising: anencryption determination means configured to determine whether or notthe magnetic card is encrypted based on encryption determination data;and an authentic signal writing means configured to encrypt the approvalsignal data when the encryption determination means determines that themagnetic card was not encrypted, and configured to write the authenticsignal data based on the approved signal data encrypted in a regionoutside of a record region of the approval signal data of the magneticrecording medium.
 4. The authenticity determination information writingdevice according to claim 3, wherein the authentic signal writing meansis configured to write the authentic signal data in at least one of afront part of the record position of a start signal data indicating astart position of the approval signal data and a rear part of the recordposition of an end signal data indicating an end position of theapproval signal data, in a region outside of the record region of theapproval signal data of the magnetic recording medium.
 5. A forged carddiscrimination device configured to discriminate whether or not amagnetic card is a forged card, the magnetic card having a magneticrecording medium in which an approval signal data for approving a cardis written in a predetermined record position, the forged carddiscrimination device comprising: an encryption determination meansconfigured to determine whether or not the magnetic card is encryptedbased on encryption determination data; an authentic signal writingdetermination means configured to determine whether or not an authenticsignal data is written in a region outside of a record region of theapproval signal data in the magnetic recording medium of the magneticcard, when the encryption determination means determined that themagnetic card was encrypted; and a forgery discrimination means whichdiscriminates whether or not the magnetic card is a forged card based onthe authentic signal writing determination means determination.
 6. Theforged card discrimination device according to claim 5, wherein theauthentic signal writing determination means is further configured todetermine whether or not an authentic signal data is written in at leastone of a front part of the record position of a start signal dataindicating a start position of the approval signal data and a rear partof the record position of an end signal data indicating an end positionof the approval signal data, in the region outside of the record regionof the approval signal data of the magnetic recording medium.
 7. Theforged card discrimination system according to claim 1, wherein theauthentic signal writing determination means is further configured todetermine whether or not an authentic signal data for determiningauthenticity of the magnetic card is written in the magnetic recordingmedium of the magnetic card, when the encryption determination meansdetermined that the magnetic card was encrypted, and wherein theauthentic signal writing means is further configured to encrypt datawritten in the magnetic recording medium to generate the authenticsignal data based on cipher generation data when the encryptiondetermination means determines that the magnetic card is not encrypted,and to write generated authentic signal data in the magnetic recordingmedium.
 8. The forged card discrimination system according to claim 7,further comprising: an encryption synchronizing signal writing meansconfigured to encrypt a synchronizing signal data written in themagnetic recording medium based on the cipher generation data andconfigured to write encrypted synchronizing signal data in the magneticrecording medium; and an encryption synchronizing signal writingdetermination means configured to determine whether or not the encryptedsynchronizing signal data is written in the magnetic recording mediumbased on the cipher generation data, when the authentic signal writingdetermination means determined that the authentic signal data waswritten in the magnetic recording medium, wherein the forgerydiscrimination means is further configured to discriminate whether ornot the magnetic card is a forged card based on the authentic signalwriting determination means determination and the encryptionsynchronizing signal writing determination means determination.
 9. Theforged card discrimination system according to claim 7, furthercomprising: an encryption synchronizing signal writing means configuredto encrypt a synchronizing signal data written in the magnetic recordingmedium based on the cipher generation data and configured to writeencrypted synchronizing signal data in the magnetic recording medium;and an encryption synchronizing signal writing determination meansconfigured to determine whether or not encrypted synchronizing signaldata is written in the magnetic recording medium based on the ciphergeneration data when the encryption determination means determined thatthe magnetic card was encrypted; wherein the forgery discriminationmeans is further configured to discriminate whether or not the magneticcard is a forged card based on the encryption synchronizing signalwriting determination means determination.
 10. The forged carddiscrimination system according to claim 7, wherein the encryptiondetermination data is a public key data set for every magnetic card, andthe encryption determination means determines that the magnetic card, inwhich the public key data is set, is encrypted when public key data isset.
 11. The forged card discrimination system according to claim 10,wherein the cipher generation data includes at least one of the approvalsignal data, the public key data, and the password data.
 12. A forgedcard discrimination system configured to discriminate whether or not amagnetic card is a forged card, the magnetic card having a magneticrecording medium in which an approval signal data for approving a cardis written in a predetermined record position, the forged carddiscrimination system comprising: a public key data writingdetermination means configured to determine whether or not a public keydata is written in the magnetic recording medium of the magnetic card; apassword data acquisition means configured to acquire a password data;an authentic signal writing determination means configured to determinewhether or not an authentic signal data for determining authenticity ofthe magnetic card is written in the magnetic recording medium of themagnetic card, based on written public key data and password dataacquired by the password data acquisition means, when the public keydata writing determination means determines that the public key data iswritten in; a public key data writing means configured to generatepublic key data and to write generated public key data in the magneticrecording medium when the public key data writing determination meansdetermined that the public key data is not written; an authentic signalwriting means configured to encrypt data written in the magneticrecording medium to generate the authentic signal data based on publickey data generated by the public key data writing means and passworddata acquired by the password data acquisition means, and to writegenerated authentic signal data in the magnetic recording medium; and aforgery discrimination means configured to discriminate whether or notthe magnetic card is a forged card based on determination results of theauthentic signal writing determination means.
 13. The forged carddiscrimination system according to claim 12, wherein the authenticsignal writing means encrypts data written in the magnetic recordingmedium based on the public key data generated by the public key datawriting means, the password data acquired by the password dataacquisition means, and the approval signal data written in the magneticrecording medium.
 14. The forged card discrimination system according toclaim 12, further comprising: an encryption synchronizing signal writingmeans configured to encrypt a synchronizing signal data written in themagnetic recording medium based on the public key data generated by thepublic key data writing means and the password data acquired by thepassword data acquisition means; and an encryption synchronizing signalwriting determination means configured to determine whether or not theencrypted synchronizing signal data is written in the magnetic recordingmedium based on the public key data generated by the public key datawriting means and the password data acquired by the password dataacquisition means, when the authentic signal writing determination meansdetermined that the authentic signal data was written, wherein theforgery discrimination means is further configured to discriminatewhether or not the magnetic card is a forged card based on determinationresult from the authentic signal writing determination means anddetermination result from the encryption synchronizing signal writingdetermination means.
 15. The forged card discrimination system accordingto claim 14, wherein the encryption synchronizing signal writing meansis configured to encrypt the synchronizing signal data by changing awidth of waveform of the synchronizing signal data written in themagnetic recording medium.
 16. The forged card discrimination systemaccording to claim 14, wherein the encryption synchronizing signalwriting means is further configured to encrypt the synchronizing signaldata in the magnetic recording medium based on all of the public keydata generated by the public key data writing means, the password dataacquired by the password acquisition means, and the approval signal datawritten in the magnetic recording medium, and the encryptionsynchronizing signal writing determination means is further configuredto determine writing presence of the encrypted synchronizing signalbased on all of the public key data generated by the public key datawriting means, the password data acquired by the password acquisitionmeans, and the approval signal data written in the magnetic recordingmedium.
 17. The forged card discrimination system according to claim 12,wherein the authentic signal writing means writes the authentic signaldata in at least one of a front part of the record position of a startsignal data indicating a start position of the approval signal data anda rear part of the record position of an end signal data indicating anend position of the approval signal data, in a region outside of therecord region of the approval signal data of the magnetic recordingmedium.
 18. The forged card discrimination system according to claim 8,wherein the encryption determination data is a public key data set forevery magnetic card, and the encryption determination means determinesthat the magnetic card, in Which the public key data is set, isencrypted when public key data is set.
 19. The forged carddiscrimination system according to claim 18, wherein the ciphergeneration data includes at least one of the approval signal data, thepublic key data, and the password data.
 20. The forged carddiscrimination system according to claim 9, wherein the encryptiondetermination data is a public key data set for every magnetic card, andthe encryption determination means determines that the magnetic card, inwhich the public key data is set, is encrypted when public key data isset; and wherein the cipher generation data includes at least one of theapproval signal data, the public key data, and the password data.